title: HIV risk in group sexual encounters: an event-level analysis from a national online survey of MSM in the U.S.
abstract: BACKGROUND
  Researchers have investigated group sexual encounters (GSEs) as potential sources for HIV/STI transmission among men who have sex with men (MSM); however, much of this work has focused on organized sex parties.
  
  
  OBJECTIVE
  To compare behavioral and social characteristics of groups of men who engaged in three types of GSEs: threesomes, spontaneous group sex, and organized sex parties.
  
  
  METHODS
  In 2012, 1,815 U.S.-based MSM completed an online survey.
  
  
  METHODS
  We compared men based on their most recent type of GSE: threesome (68.2%), spontaneous group sex (19.7%), or organized sex party (12.1%).
  
  
  RESULTS
  Using multinomial logistic regression, with type of GSE as the dependent variable, MSM who were HIV-positive, used stimulants (cocaine, methamphetamine, crack), consumed five or more alcoholic drinks, and reported receptive unprotected anal intercourse (UAI) during the most recent GSE had significantly higher odds of having had spontaneous group sex as compared to a threesome. MSM who were HIV-positive, not in a relationship, and did not report receptive UAI during the most recent GSE had significantly higher odds of having attended an organized sex party as compared to a threesome. MSM who were in a relationship, had consumed five or more alcoholic drinks, had used stimulants, and reported receptive UAI during the most recent GSE had significantly higher odds of having had spontaneous group sex as compared to an organized sex party. Compared to others, those having engaged in a GSE were more likely to report recent UAI (65% vs. 45%).
  
  
  CONCLUSIONS
  Men having engaged in a GSE were at greater risk for behaviors that transmit HIV and STIs. Unique social and behavioral characteristics inherent to threesomes, spontaneous group sex, and sex parties highlight the need to identify prevention strategies to help those who participate in GSEs reduce their risk for HIV and STI transmission.
authors.affiliation: Department of Health and Nutrition Sciences, Brooklyn College, City University of New York, New York, NY, USA; Center for HIV/AIDS Educational Studies and Training (CHEST), New York, NY, USA; CUNY School of Public Health, The Graduate Center of CUNY, New York, NY, USA.
authors.forename: Christian
authors.initials: C
authors.lastname: Grov
authors.forename: H Jonathon
authors.initials: HJ
authors.lastname: Rendina
authors.forename: Ana
authors.initials: A
authors.lastname: Ventuneac
authors.forename: Jeffrey T
authors.initials: JT
authors.lastname: Parsons
mesh_terms: D000328:Adult; D000428:Alcohol Drinking / Q000009:adverse effects / Q000453:epidemiology; D019969:Amphetamine-Related Disorders / Q000453:epidemiology; D019970:Cocaine-Related Disorders / Q000453:epidemiology; D006126:Group Processes; D015658:HIV Infections / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology / Q000635:transmission*; D006306:Health Surveys; D018451:Homosexuality, Male / Q000523:psychology / Q000706:statistics & numerical data; D006801:Humans; D020407:Internet; D008297:Male; D012309:Risk-Taking; D012747:Sexual Partners / Q000523:psychology; D012919:Social Behavior; D014481:United States / Q000453:epidemiology; D047568:Unsafe Sex / Q000523:psychology / Q000706:statistics & numerical data; D055815:Young Adult
keywords: Gay and Bisexual Men; Group Sex; Men Who Have Sex with Men; Sex Parties; Substance Use; Unprotected Anal Intercourse